91Ó°ÊÓ

Electronegativity of an atom is defined as the tendency of an atom to attack the electrons.

In the periodic table as we move from right to left in a period electronegativity goes on increasing. While in a group as we move downward electronegativity is decreases. This is the general trend found in the periodic table. The relation of acidic character with electronegativity is as follows;

Electronegativity $\mathrm{Î\pm }$ acidic character

The relation of acidic character with electronegativity is as follows;

Electronegativity$\mathrm{Î\pm }$acidic character

In a group, as we move downward electronegativity is decreases.So nitrogen is more negative than phosphorus and is more electronegative than arsenic. Hence the order of acidity for the given acids is as follows;

${\mathrm{HNO}}_3>{\mathrm{H}}_3{\mathrm{PO}}_4>{\mathrm{H}}_3{\mathrm{AsO}}_4$

So nitric acid is most acidic one.